1,732,433 research outputs found
Scheduling of waiting queues in manufacturing workprocess using a human reliability measure
No full textIn the recent years the increasing recognition of the critical role of human factor in complex manufacturing
systems, has focused a new attention towards the Human Reliability Analysis (HRA). During the phases of
operations scheduling, engineers usually focus on problems caused by hardware, software or machinery
breakdowns and they seldom pay attention to problems caused by the human error, which significantly may
affect not only system reliability and safety but also the effectiveness of scheduling. The objective of the research
is to look for a job sequence, in a waiting queue, able to improve the economic “expected profit”, considering
the natural downsizing of the human performances during the workshift. Starting from a sequence of scheduled
jobs, the model analyses the human error probability (HEP) for each manual operation, and assesses its error
effects on the whole system. The model initially searches for the best job to be worked by the operator,
according to his reliability and specific HEP value; moreover it automatically determines, for that operator, the
optimal distribution of work pauses. The pauses are calculated in function of boundary causes that influence the
human reliability and are focused on the reduction of HEP. The proposed methodology determine, if it exists,
the optimal work sequence, that minimizes the HEP maximizing its deriving value of the global function of
profit
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Cytologic observations preceding high grade squamous intraepithelial lesions.
No full textThere is some evidence that a significant proportion (12\%) of women, prospectively followed after negative cervical cytologic findings, develop tissue-proven high grade squamous intraepithelial neoplasia (HSIL) within a short period (up to 24 months). The present study was undertaken to address the validity of this statement since such a high prevalence of spontaneous HSIL, if true, may challenge the value of an annual cervicovaginal cytologic smear examination. Cytologic smears collected from 82 patients with tissue-proven HSIL and obtained in the preceding 24 months were evaluated. The vast majority (90\%) of these smears revealed evidence of cervical epithelial abnormalities prior to the development of HSIL-88\% at 24 months and 96\% at 12 months. The cytomorphologic features of low grade squamous intraepithelial neoplasia were observed in 45\% of the smears, while the remaining cases were not normal or negative but had cytologic evidence of human papillomavirus (HPV)-associated changes (described elsewhere), including binucleation and multinucleation, epithelial plaques and pearl formations, and hyperkeratosis, dyskeratosis and parakeratosis. Persistent negative cytology was found in only three cases. Although these HPV-related cellular changes may not have an independent predictive value for HSIL, our study demonstrated that their awareness and detection can help to identify women at risk of potentially more advanced lesions. Thus, an annual cytologic smear examination is valuable and accurately reflects the presence of HPV-associated epithelial changes and precursor lesions of HSIL
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Extensions of Natural Radioactivity to 4th-Type and of the Periodic Table to Super-heavy Nuclei: Contribution of Raj K Gupta to Cold Nuclear Phenomena
Get PDFWe have studied here the contribution of Indian Scientists associated with Prof. Raj K. Gupta to cold nuclear phenomena during the last almost four decades, which led to the discovery of fourth kind of natural radioactivity (also known as Cluster Radioactivity, CR) and to the extension of periodic table to super heavy nuclei. It is exclusively pointed out how the Quantum Mechanical Fragmentation Theory (QMFT) advanced by Prof. Raj K. Gupta and Collaborators led to the discovery of unique phenomenon of CR along with the predictions leading to the synthesis of super heavy elements. We have also mentioned the development of dynamical theories based on QMFT, the Preformed Cluster Model(PCM) and the dynamical cluster-decay model (DCM), to study the ground and excited state decays of nuclei, respectively, by Gupta and Collaborators. It is matter of great honor and pride for us to bring out this study to enthuse the young researchers to come up with novel ideas and have inspiration from the scientific contributions of Prof. Raj K. Gupta who is coincidentally celebrating his platinum jubilee birthday anniversary this year
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
